A number of information processing devices not only performs a single process, but also performs a plurality of processes. Accordingly, there are various techniques studied relating to the management of a process such as resource distribution, process scheduling, etc. among processes.
For example, the following controller is proposed for one information processing device to realize both the guarantee of real time control processing and throughput of network communication processing.
A controller manages a plurality of tasks after dividing the tasks into two groups, that is, a communication task group for communication with a network communication system and a control task group for monitor control of a monitoring control target. Furthermore, the controller switches the execution order for a plurality of tasks in group units, and processes information obtained from a monitoring control target or a network communication system based on the switched task group.
Furthermore proposed is the following technique to easily, automatically, and maximally derive the responsiveness of an application to be processed based on time shared scheduling even in an environment in which the number of executed applications frequently increases or decreases.
In this technique, an application dependence analysis unit executes as a node the processing from the start to the pause in the process of the operation in time shared scheduling, analyzes the dependence among nodes, and generates dependence analysis information indicating the execution order and the dependence of nodes. Furthermore, a control change judgment unit transfers the process which configures an application from time shared scheduling to group scheduling according to dependence analysis information. Then, a group scheduling execution unit performs group scheduling in process units for the transferred process according to the dependence analysis information.
Furthermore, the following technique is proposed to prevent a reversal phenomenon in task priority with an increasing overhead suppressed as much as possible.
During the exclusive use of shared resources by a first task having a low priority through a resource management device, a request to use the same shared resources may be issued from a second task having a high priority. In this case, the task management device temporarily changes the priority of the first task into the priority of the second task while the use of the shared resources is completed.
The reversal phenomenon of task priorities is suppressed by the temporary change of priorities. That is, suppressed is the reversal phenomenon that “an interrupt from a third task having an intermediate priority during the use of the shared resources by the first task delays the processing of the first task, and consequently the third task is processed before the second task which has a higher priority than the third task.”
Furthermore proposed is the following information terminal device to realize a comfortable operation environment by solving the problem of a small capacity of memory when plural pieces of application software are started.
The information terminal device sets resident or temporary attribute information for plural pieces of application software loaded into the information terminal device, and manages the attribute information using a table with the attribute information associated with the application software which is currently being operated. In addition, at the start of an application, the information terminal device refers to the table and judges the attribute information set in the currently operated application software.
Then, the information terminal device leaves the application software whose resident attribute information is set in the execution memory as is, forcibly terminates the application software whose temporary attribute information is set, and releases the software from the execution memory, thereby avoiding the problems that “the memory capacity becomes insufficient by using a number of pieces of application software, the executing operation becomes slow, and software may run away.”
The following documents are well known.    Japanese Laid-open Patent Publication No. 2003-67201    Japanese Laid-open Patent Publication No. 2009-48358    Japanese Laid-open Patent Publication No. 8-77025    Japanese Laid-open Patent Publication No. 2003-15892